Generally, a sliver to be spun into yarn is delivered in cans to open-end spinning frames. The cans are deposited underneath the spinning stations and the sliver is introduced from the can to the spinning station. The cans as a rule are wide as two adjoining spinning stations, so that two adjoining spinning stations are supplied with sliver from two sliver cans resting one behind the other, thereby creating two rows of sliver cans along the length of the machine.
In spinning machines wherein the supply of sliver cans to and the changing of the sliver cans at the spinning stations is automated, the changing of an empty can in the second row (I.e. Closest to the spinning stations) requires a particular technical effort if the disposition of the sliver can in the first row in relation to the spinning station is to be preserved. An example of this type of automated machine is shown and described in German Patent Publication DE 41 25 383 A1.
A yarn break occurs when a sliver can runs out of sliver. A piecing carriage is then called to the spinning station to repair the yarn break. However, the yarn break cannot be fixed by repiecing the sliver because the sliver is missing. The piecing carriage therefore leaves the spinning station and signals a request for delivery of a full sliver can to that spinning station. The piecing carriage is returned to the spinning station only after the replacement sliver can has arrived in order to thread the sliver (if sliver threading is automated) and to perform the piecing process. The supply of the spinning stations with sliver in this way is time-consuming and reduces the effective use of each respective spinning station during sliver can changes.